基于虚拟样机技术的飞机起落架着陆载荷分析

起落架是飞机重要的承载机构，其在飞机的起飞、降落和着陆过程中担负着十分重要的作用。起落架着陆载荷是指在飞机着陆瞬间起落架所承受的地面载荷，根据位置的不同可分为轮胎接地点载荷、轮轴点载荷和交点载荷。飞机设计重量（包括空机重量、商载和燃油重量）的分布变化会对起落架着陆载荷产生影响。以典型民用飞机的起落架为研究对象，基于虚拟样机技术对起落架模型进行着陆分析。首先利用HyperMesh、MSC.Nastran软件对飞机起落架模型进行前处理和简化，然后根据中国民用航空规章运输类飞机适航标准相关条目要求，在MSC.ADAMS软件中设置相应的工况参数并进行起落架着陆动力学仿真分析，研究不同燃油密度下飞机的重量和重心变化对起落架轮轴点着陆载荷的影响。通过对比仿真结果可以发现：飞机的重量和重心变化对起落架轮轴点着陆载荷产生了明显的影响，而燃油密度变化对起落架轮轴点着陆载荷的影响较弱。研究结果可为今后有针对性地开展起落架着陆载荷计算提供参考和指导。

Analysis of landing load of aircraft landing gear based on virtual prototype technology

As an important bearing mechanism of the aircraft, the landing gear plays a very important role in the process of aircraft take-off and landing. The landing load of landing gear refers to the ground load borne by the landing gear at the moment of aircraft landing, which can be divided into tire contact point load, wheel axle point load and intersection load according to different positions. Changes in the distribution of the design weight of aircraft (including empty weight, commercial load and fuel weight) will affect the landing load of landing gear. Taking the landing gear of a typical civil aircraft as the research object, the landing analysis for the landing gear model was carried out based on the virtual prototype technology. Firstly, the HyperMesh and MSC.Nastran software were used to pre-process and simplify the aircraft landing gear model. Then, according to the requirements of relevant items of airworthiness standards for transport aircrafts in China’s civil aviation regulations, the corresponding working condition parameters were set up and the landing gear landing dynamics simulation was carried out in the MSC.ADAMS software, so as to research the influence of the change of weight and gravity center of the aircraft on landing gear wheel axle point landing load under different fuel densities. By comparing the simulation results, it could be found that the change of weight and gravity center of the aircraft had a significant influence on the wheel axle point landing load of landing gear, while the change of fuel density had a weak influence on the wheel axle point landing load of landing gear. The research results can provide reference and guidance for the targeted calculation of landing gear landing load in the future.